Neuromyelitis optica (NMO) is an inflammatory disease of the central nervous system that is associated with autoantibodies to aquaporin-4. Treatment options for prevention of clinical relapses of NMO include immunosuppressive medications. Plasma exchange (PLEX) is commonly used as a rescue therapy for NMO relapses but ongoing, regular PLEX procedures (maintenance PLEX) is sometimes used to prevent relapses. This observational registry will record feasibility, tolerability, safety, and preliminary efficacy data regarding maintenance PLEX for NMO.

Neuromyelitis optica (NMO) is an inflammatory disease of the central nervous system that is associated with autoantibodies to aquaporin-4. Treatment options for prevention of clinical relapses of NMO include immunosuppressive medications. Plasma exchange (PLEX) is commonly used as a rescue therapy for NMO relapses but ongoing, regular PLEX procedures (maintenance PLEX) is sometimes used to prevent relapses. This observational registry will record feasibility, tolerability, safety, and preliminary efficacy data regarding maintenance PLEX for participants with NMO, NMO spectrum disorders, and recurrent idiopathic longitudinally extensive transverse myelitis.

Inclusion Criteria:

• Neuromyelitis optica
• Neuromyelitis optica spectrum disorder
• Recurrent idiopathic longitudinally extensive myelitis
• Age 18 years or greater

Exclusion Criteria:

• Any condition that in the opinion of the investigator could increase a participant's risk by participating in the observational study or confound the outcome of the study

Neuromyelitis optica/CNS demyelinating disease specialty clinics